Percussion-rotary drilling mechanism with mud drive turbine

ABSTRACT

A percussion-rotary drilling mechanism comprising a rotary drill bit and a percussion drill bit is disclosed with a mud driven turbine wheel for actuating the latter drill bit. Likewise, two reciprocators for receiving rotary motion from the turbine wheel and for generating reciprocal movement in the percussion drill bit portion of the percussion-rotary drilling mechanism comprise an arcuate cam and cam follower drive mechanism and a rotatable eccentrically weighted wheel drive mechanism.

United States Patent 1 1 Pogonowski et a].

[451 Apr. 30, 1974 [5 PERCUSSION-ROTARY DRILLING 1,861,042 5/1932 Zublin175/296 MECHANISM WITH, MUD DRIVE TURBINE 3,193,027 7/1965 Bodine l75/57[75] Inventors: Ivo C. P onowski, Blacksbur Va.;

Fuad T. S aadeh Houston Ta Pnmm Leppmk Attorney, Agent, or Firm-T. H.Whaley; C. G. Ries [73] Assignee: Texaco Inc., New York, NY.

[22] Filed: Dec. 29, 1972 [57] ABSTRACT [21] Appl. No.: 319,259 Apercussion-rotary drilling mechanism comprising a rotary drill bit and apercussion drill bit is disclosed with a mud driven turbine wheel foractuating the lat- 5 1 2 33 ter drill bit. Likewise, two reciprocatorsfor receiving 58] Fieid 106 107 rotary motion from the turbine wheel andfor generating reciprocal movement in the percussion drill bit [56]References Cited portion of the percussion-rotary drilling mechanismcomprise an arcuate cam and cam follower drive UNITED STATES PATENTSmechanism and a rotatable eccentrically weighted 2,868,511 1/1959Barrett 175/296 wheel drive mechanism 2,942,85l 6/1960 Beck 2,970,6602/l96l Bodine, Jr 175/56 11 Claims, 13 Drawing Figures /fl 2 h :i s z:

H I x H /5 E E E 2/ 1632-7! PERCUSSION-ROTARY DRILLING MECHANISM WITHMUD DRIVE TURBINE BACKGROUND OF THE INVENTION OBJECTS OF THE INVENTIONAccordingly, a principal object of this invention is to provide animproved drive means for a drill bit mechanism for use in a drill stringfor drilling a well through the subsurface stratigraphy.

Another principal object of this invention is to provide a mud driventurbine motor for driving a percussion type drill bit to augment thebottom hole delivered horsepower in rotary drilling.

A further object of this invention is to provide a rotary cam and camfollower means for transmission of the rotary movement from a mud driventurbine to a reciprocating percussion type drill bit of apercussionrotary drilling mechanism.

Another and alternate object of this invention is to provide a rotatableeccentric weight reciprocator for transmission of the mud driven turbinerotary motion to a reciprocating percussion drill bit of avibratoryrotary drilling mechanism.

A still further object of this invention is to provide an improveddrilling mechanism utilizing a mud driven turbine which is easy tooperate, is of simple configuration, is economical to build andassemble, and is of greater efficiency for drilling through hard rock.

BRIEF DESCRIPTION OF THE DRAWINGS The drawings diagrammaticallyillustrate by way of example, not by way of limitation, three forms ormechanisms of the invention wherein like reference numerals have beenemployed to indicate similar parts in the several views in which:

FIG. 1 is a schematic vertical view of the invention with parts insection when incorporated in an oil or gas well being drilled;

FIG. 2 is a schematic vertical sectional view of the invention taken at2-2 on FIG. 1;

FIG. 3 is a schematic vertical sectional view taken at 3-3 on FIG. 2;

FIG. 4 is a schematic sectional view of the invention taken at 4-4 onFIG. 1, with the percussion drill bit illustrated in its loweredposition;

FIG. 5 is a view similar to FIG. 4 but with the percussion drill bitillustrated in its upper position;

FIG. 6 is a schematic bottom view of the invention taken at 6-6 on FIG.1;

FIG. 7 is a schematic sectional view of the invention taken at 7-7 onFIG. 4;

FIG. 8 is a schematic sectional view of the invention taken at 8-8 onFIG. 4;

FIG. 9 is a schematic longitudinal sectional view of a modification ofthe invention of FIG. 4, with the percussion drill bit illustrated inits lowered position;

FIG. 10 is a schematic sectional view similar to FIG. 9, but with thepercussion drill bit illustrated in its upper position;

FIG. 11 is a schematic sectional view of the invention taken at 1 111 onFIG. 9 having two rows of eccentric weights;

FIG. 12 is a schematic'detailed perspective view of one of the rotatableeccentric weights of the modification of FIG. 9; and I FIG. 13 is aschematic sectional view of another mod ification of the invention,similar to FIG. 11 but having four rows of eccentric weights.

DESCRIPTION OF THE INVENTION The invention disclosed herein, the scopeof which being defined in the appended claims, is not limited in itsapplication to the details of construction and arrangements of partsshown and described, since the invention is capable of other embodimentsand of being practiced or carried out in various other ways. Also, it isto be understood that the phraseology or terminology employed herein isfor the purpose of description and not of limitation. Further, manymodifications and variations of the invention as hereinbefore set forthwill occur to those skilled in the art. Therefore, all suchmodifications and variations which are within the spirit and scope ofthe invention herein are included and only such limitations should beimposed as are indicated in the appended claims.

The drawings disclose three embodiments of the invention for drilling awell, such as but not limited to an oil or gas well through hard rockparticularly.

DESCRIPTION OF ONE EMBODIMENT OF THE DRILLING MECHANISM OF FIG. 1

FIG. 1, a schematic, vertical sectional view of one embodiment of theinventive drilling mechanism 10, discloses a drill collar 11 comprisingupper and lower portions, 11a and 11b, respectively, attached with aconnector 12 to the bottom of a drill pipe (not shown) and having adrill bit mechanism 13 for forming the lower end of a drill string fordrilling a wellbore 14.

One of'the main features of this'invention is the mud turbine 15, FIG.1, driven by the downward flow of the drilling fluid or mud entering thedrill collar 10 at the top through the connector 12 and passing throughthe drill collar to the drill bit mechanism 13 from where the drillingmud picks up the rock chips and heat as it is forced up to the surfacethrough the annulus formed between the drill string and the wellbore.

MUD TURBINE Mud turbine 15, FIG. 1, is mounted in upper and lower thrustbearings 16a and 16b, respectively and is telescopically connected tothe drill bitmechanism 13 through a reciprocator to the drill bit 17 inthe lower portion 1 1b of the drilling mechanism 10. FIG. 2, a sec tionat 2-2 on FIG. 1, shows greater details of the mud turbine 15, aconventional turbine driven by the downward flow of drilling mud in thedrill string and having conventional upper and lower seals 18a, 18b.Upper and lower bearings 16a and 16b are conventional bearings fixedlymounted in the drill collar with set screws 19 protruding intosubstantially enantiomorphic bearing retainers or housings a, 20b forholding ball bearings 21. On the bottom of mud turbine 15, FIG. 2, isformed an extension 22, FIG. 3, particularly, having a square hole 23for slideably receiving a square end 24a, FIG.'4, of square ended shaft24 from the reciprocator 17, FIG. 1. Further, if the design so dictates,a male and female spline drive may be utilized.

COMBINATION DRILL BIT 2,868,51 1. Further, a positive, mechanicalconnection throughout the disclosed reciprocator is described hereinafter showing it to be a definite improvement over the usual compressedair device as shown in the above-identified patent.

FIG. 3, a sectional view at 33 on FIG. 2, illustrates lower bearing 16bhaving three mud passages 27b and the square hole 23 internally of mudturbine extension 22. Likewise, upper bearing 16a, FIG. 2, has threesimilar mud passages 27a.

RECIPROCATOR OF FIG. 4 The, reciprocator 17, FIG. 1, comprises basicallycams and cam followers for generating reciprocal movement in thepercussion drill bit 26. In greater detail, square shaft end 24a, FIG.4, is the upper end of elongated square ended shaft 24 mounted insuitable bearings 28a, 28b, 28c, and terminating at the bottom with acam plate 29 connected to shaft lower square end 24b and having twosemicircular incline planes 29a and 291), FIG. 7, all of which are thusrotated by the mud turbine through its extension 22, FIG. 4, asillustrated.

Drill collar lower portion 11b, FIG. 4, has a cup shaped sleeve 30slideable therein, the sleeve having inward projecting axles 31a, 31bwith cam rollers 32a, 32b, mounted thereon for rolling on thesemicircular inclined planes 29a, 29b, FIG. 7. Thus withcounterclockwise rotation of the cam 29 on shaft 24, FIGS. 4 and 7, thecam rollers 32a, 32b roll up the inclined lanes 29a, 29b with each halfturn to raise the sleeve 30 by the height of the cam surfacesillustrated in FIG. 5,

prior to both cam rollers dropping off simultaneously to adjacent thecam lower surface. A compression spring 33 mounted between the top ofthe cup shaped sleeve 30 and the bottom of a bearing retainer 34accelerates downward movement of sleeve 30 when the rollers 32a, 32broll off the inclined planes 29a, 29b.

Cup shaped sleeve 30, FIG. 4, has thick sides, thick bottom, and heavyplates 35a 350 secured therein, as by a nut on a threaded upper endportion 36a of percussion drill bit shaft 36 for increased momentum orinertiaA guide rod 37 maintains plates 35a 35c with their respectivedrilling mud passages 38a 380 in proper alignment. Thus drilling mudflows from the drill string through the mud turbine 15, FIG. 1, downthrough mud passages 34a, FIG. 4, in bearing retainer 34, through camplate mud passages 29c, FIGS. 4 and 7, through plate mud passages 37a37c, FIG. 4, and

through drill bit mud passages 13a, FIG. 1, to the drill bits 25 and 26of the drill bit mechanism 13 for carrying rock chips and heat back tothe surface.

FIG. 7, a sectional view at 7-7 on FIG. 4, along with FIG. 4 and 5,particularly illustrate the cam plate inclined surfaces 29a and 29b.

FIG. 8, a sectional view at 8-8 on FIG. 4, illustrates the three mudpassages 37a in top weight 35a in sleeve 30, the latter having splines30a and 30b slideable in the drill collar lower portion 1 1b forpermitting vertical longitudinal movement of the sleeve relative to thedrill collar, but preventing rotational relative movement between thetwo cylindrical elements.

Briefly, in operation of the vibratory-rotary drilling mechanism withthe mud driven turbine of the embodiment of FIGS. l-8, the drill collar11, FIG. 1, is rotated by the drill pipes (not shown) of the drillstring for rotating the roller bits 25 in the conventional manner.Combined with the roller drill bit 25 is the three prong percussiondrill bit 26, which in addition to the chiseling action at the centerhas chisel prongs 26a 26c positioned in between each of the roller bitcones 25a 25c for greater efficiency.

A principal feature is the mud turbine drive mechanism and oneembodiment of a reciprocator driven thereby, for driving the percussiondrill hit. As the mud flows through the drill collar and through thefull length of the mud turbine 15, it is rotated with great force forrotating cam plate 29. With the gradual rise and sudden fall of the camfollowers and percussion drill bit connected thereto, hard blows resultwith this chisel bit, particularly from the spring action and addedweights, all operated from the rotation imparted by new mud turbine. Theresult is a very fast and efficeint drilling mechanism.

Cam plate 29, FIG. 4, may be spaced slightly below the lowest positionof the cam rollers when the percussion bit is resting on the bottom, ifso desired, to insure that all downward force is absorbed by the hardrock well bottom.

RECIPROCATOR OF FIGS. 9 AND 10 FIG. 9 discloses a second type ofreciprocator 40 which is driven by the new and same mud turbine 15 fortransmitting powerful vibratory motion to the percussion drill bit shaft36b which is attached to the percussion drill bit (not shown), thelatter percussion drill bit being identical to that, 25, of the firstembodiment.

Mud turbine 15, FIG. 9, mounted in lower thrust bearing 16b has anelongated square hole 15a for slideably connecting thereto a square end42a of worm drive 42, similar to the corresponding mud turbine lowerslideable connection of the first embodiment of FIG. 1, wherebysubstantial length is provided in the slideable connection of the wormdrive to permit oscillation thereof in the vertical direction. Likewiseif so desired, a spline drive may be utilized on the bottom of the mudturbine.

Reciprocator 40, FIG. 9, comprises a housing 43 for mounting a pluralityof eccentric weights for vibrating or oscillating the housing in avertical direction for supplying powerful and strong reciprocal movementto the percussion drill bit (not shown) for drilling therewith incombination with the roller drill bit (not shown). I-Iousing 43, FIG.11, a sectional view at 11-11 on FIG. 9, has vertical splines 44a, 44b,slideable in correspondingly shaped grooves 45a, 45b in the drill collarlower portion 11b, FIG. 9, for maintaining the percussion drill bitequally spaced between the roller bit cones as will be evidenthereinafter.

Ten eccentric weights, for example, each like eccentric weight 46 havinga worm gear formed integral therewith as illustrated in FIG. 12, aremounted on axles 47, FIGS. 9 -l1, in suitable bearings in housing 43,FIGS. 9, 11, in a vertical row of horizontal pairs with the verticalworm drive separating, but in operable contact with, the eccentricweight worm gears of each pair, eccentric weights 46a and 46b mountedon'the respective axles 47a and 47b being typical. Stud 48, FIG. 9,fixedly connects the bottom of housing'43 to percussion drill bit shaft36b.

After the mud has passed downwardly through the mud turbine 15, FIG. 9,it passes through mud passages 160 in lower bearing retainer 16b,downsides of reciprocator housing 43, FIG. 11, through mud passages 43b,FIGS. 9 and 11, in housing bottom 43a, and through the bottom of thedrill collar to the drill bits as shown in FIG. 1.

Briefly, in operation of the percussion-rotary drilling mechanism withthe mud driven turbine of the embodiment of FIGS. 9 12, the roller bitsare rotated by the rotating drill collar in the conventional manner.Combined with the roller drill bit is the three prong percussion drillbit, like the first embodiment, having the three chisel equally spacedbetween the three roller bit cones for providing a chiseling in the conearea in addition to the chiseling action at the center for increasedefficiency.

Likewise, the mud turbine combined and utilized with the two drill bitsprovides an outstanding drilling mechanism. Thus with all eccentricweights mounted identically to each other on the worm drive 42, as theyall are rotating together and when their heavy sides come down, asillustrated in FIG. 9, the housing 43 and accordingly the percussiondrill 36b is driven or forced down with great force. With the rotationof the heavy side of the eccentric weights to the upper position shownin FIG. 10, the reciprocator 40 as well as the precussion drill bit areraised to gain momentum for the next downward blow.

Thus due to the hammering action generated by the reciprocator 40 asoperated by rotation efficiently imparted by the new mud turbine, theresult is a fast, reliable, simple, and economical precussion-rotarydrilling mechanism.

FIG. 13 illustrates a third modification in which eccentric weightedwheel housing 43a is cruciform in shape providing twice the number ofeccentric weights, as one horizontal plane of weights 46a 46d, to beutilized and driven by the mud turbine for increased drilling force.

It is known that for a well that requires 9 hours to drill solely with apercussion type of chisel drill bit by known drilling methods, and for asimilar well that requires 3 hours to drill solely with a rotary orthree roller cone drill bit, that by reciprocally adding the time todrill a similar well with both bits simultaneously, the time required is2-5 hours. However, by utilizing the disclosed improved drillingmechanism including the mud driven turbine and either of the modififedreciprocators, it is estimated that the drilling time for a similar wellis cut to 1-% hours.

While only three mechanisms have been disclosed, it

will be evident that various other modifications are possible in thearrangement and construction of the disclosed drilling mechanismswithout departing from the,

scope of the invention and it is accordingly desired to comprehendwithin the purview of this invention such modifications as may beconsidered to fall within the scope of the appended claims.

We claim:

1. A drill string having drilling mud flowing downwardly and internallythereof comprising:

a. drill collar means having an upper portion and a lower portion in thedrill string for receiving drilling mud therethrough,

b. drill bit means for said lower portion of said drill collar means forreceiving said drilling mud,

c. mud driven turbine means rotatably mounted in said upper portion ofsaid drill collar means for being rotated by said drilling mud foroperation of said drill bit means,

d. said drill bit means comprises a rotary drill bit means and apercussion drill bit means,

e. said rotary drill bit means comprises a plurality of spaced apartroller bits,

f. said percussion drill bit means comprises the same number of prongsas roller bits extending laterally from the bottom of a vertical shaftextending downwardly from said mud driven turbine-means and is operableby said rotating mud driven turbine means, and

g. each of said percussion drill bit means prongs is equally spacedbetween said roller bits for providing a very efficientpercussion-rotary drilling mechanism.

2. A drill string as recited in claim 1 wherein said drill collar meanshas a longitudinal axis and wherein,

a. said percussion drill bit means is responsive to said rotating muddriven turbine means for reciprocal movement in a direction parallel tothe drill collar means longitudinal axis.

3.'A drill string as recited in claim 1 wherein,

a. saidmud driven turbine means has a rotary cam connected thereto forbeing rotated therewith, and

b. said percussion bit means has a cam follower moveably mounted on saidrotarycam for generating reciprocal movement in said percussion bitmeans.

4. A drill string as recited in claim 1 wherein,

a. said mud driven turbine means has a rotatable eccentric weightreciprocator means connected thereto for being reciprocated and vibratedthereby; and

b. said percussion bit means is connected to said rotatable eccentricweight reciprocator for being reciprocated thereby.

5. A drill string having a plurality of drill pipes with drilling mudflowing downwardly and internally thereof to the bottom comprising,

a. a drill collar attached to the lower end of the lowest drill pipe forreceiving a drilling mud therethrough from above,

b. a drill bit mechanism mounted on a lower end of said drill collar forreceiving said drilling mud,

c. mud driven turbine means rotatably mounted in an upper portion ofsaid drill collar for being rotated by said drilling mud as it passesdown to said drilling mechanism,

d. said mud driven turbine means is connected to said drilling mechanismfor operation thereof about the center line of rotation of said mudturbine,

e. said drill bit mechanism comprises a rotary bit means and apercussion bit means,

f. said rotary bit means comprises three spaced apart roller bitsrotatably mounted to the lower portion of said drill collar,

g. said percussion bit means comprises three prongs extending laterallyfrom the bottom of a vertical shaft extending downwardly from said muddriven turbine means,

h. each of said percussion drill bit means three prongs is equallyspaced between said three roller bits, and

i. said percussion bit means is responsive to said mud driven turbinemeans for reciprocal movement between said spaced apart roller bits forproviding a very efficient percussion-rotary drilling mechanism.

6. A drill string as recited in claim wherein,

a. said mud driven turbine means has a rotary cam connected thereto forbeing rotated therewith, and

b. said percussion bit means has a cam follower moveably mounted on saidrotary cam for generating reciprocal movement in said percussion bitmeans.

7. A drill string as recited in claim 5 wherein,

a. said mud driven turbine means has a rotatable eccentric weightreciprocator means connected thereto for being reciprocated thereby, and

' b. said percussion bit means is connected to said rotatable eccentricweight reciprocator for being reciprocated thereby.

8. A drill string as recited in claim 5 wherein,

a. said elongated turbine wheel lower end has an arcuate cam fixedthereto for rotation therewith, and

b. said drill bit mechanism has a cam follower roller mounted on saidarcuate cam for generating reciprocal movement in said drill bitmechanism as said arcuate cam rotates with said mud driven elongatedturbine wheel.

9. A drill string having a plurality of drill pipes with drilling mudflowing downwardly and internally thereof to the bottom comprising,

a. a drill collar attached to the lower end of the lowest drill pipe forreceiving a drilling mud therethrough from above, I

b. a drill bit mechanism mounted on a lower end of sai drill collar forreceiving said drilling mud,

c. mud driven turbine means rotatably mounted in an upper portion ofsaid drill collar for being rotated by said drilling mud as it passesdown to said drilling mechanism,

d. said mud driven turbine means is connected to said drilling mechanismfor operation thereof about the center line of rotation of said mudturbine,

c. said mud driven turbine means comprises an elongated turbine rotorhaving upper and lower ends mounted axially in said drill collar inbearings at each of said ends of said elongated turbine wheel,

f. said elongated turbine wheel lower end is connected to said drill bitmechanism for operation thereof,

g. said elongated turbine wheel lower end has a rotary eccentric weightreciprocating mechanism connected thereto comprising a worm drive inrotating contact with a worm gear fixed to an eccentric weight forgenerating reciprocal motion with rotation of said elongated turbinewheel lower end, and

h. said drill bit mechanism has a percussion bit means fixed to saidrotary eccentric weight reciprocating mechanism for being reciprocatedthereby with rotation of said mud driven elongated turbine wheel.

10. A percussion-rotary drilling mechanism as recited in claim 9 whereinsaid reciprocator means comprises, I

a. a cam plate connected to the bottom of said mud driven turbine meansto rotate therewith, and

b. cam rollers mounted on said percussion drilling means and operable onsaid rotatable cam plate for generating reciprocal movement in saidpercussion drilling means.

11. A percussion-rotary drilling mechanism having a plurality of drillpipes with drilling mud flowing downwardly and internally thereof to thebottom comprising,

a. a drill collar attached to the lower end of the lowest drill pipe forreceiving a drilling mud therethrough from above,

b. a drill bit mechanism mounted on a lower end of said drill collar forreceiving said drilling mud,

c. mud driven turbine means rotatably mounted in an upper portion ofsaid drill collar for. being rotated by said drilling mud as it passesdown to said drilling mechanism, 1

d. said mud driven turbine means is connected to said drilling mechanismfor operation thereof about the center line of rotation of said mudturbine,

e. said mud driven turbine means comprises an elongated turbine rotorhaving upper and lower ends mounted axially in said drill collar inbearings at each of said ends of said elongated turbine wheel,

f. an eccentric weight having a worm gear fixed thereto and rotatablymounted on said percussion drilling means,

g. a worm drive mounted on the bottom of said mud driven turbine meansto rotate therewith, and

h. said rotatable eccentric weight worm gear being mounted in operableengagement with said rotating worm drive for generating reciprocalmovement in said percussion drilling means.

1. A drill string having drilling mud flowing downwardly and internallythereof comprising: a. drill collar means having an upper portion and alower portion in the drill string for receiving drilling mudtherethrough, b. drill bit means for said lower portion of said drillcollar means for receiving said drilling mud, c. mud driven turbinemeans rotatably mounted in said upper portion of said drill collar meansfor being rotated by said drilling mud for operation of said drill bitmeans, d. said drill bit means comprises a rotary drill bit means and apercussion drill bit means, e. said rotary drill bit means comprises aplurality of spaced apart roller bits, f. said percussion drill bitmeans comprises the same number of prongs as roller bits extendinglaterally from the bottom of a vertical shaft extending downwardly fromsaid mud driven turbine means and is operable by said rotating muddriven turbine means, and g. each of said percussion drill bit meansprongs is equally spaced between said roller bits for providing a veryefficient percussion-rotary drilling mechanism.
 2. A drill string asrecited in claim 1 wherein said drill collar means has a longitudinalaxis and wherein, a. said percussion drill bit means is responsive tosaid rotating mud driven turbine means for reciprocal movement in adirection parallel to the drill collar means longitudinal axis.
 3. Adrill string as recited in claim 1 wherein, a. said mud driven turbinemeans has a rotary cam connected thereto for being rotated therewith,and b. said percussion bit means has a cam follower moveably mounted onsaid rotary cam for generating reciprocal movement in said percussionbit means.
 4. A drill string as recited in claim 1 wherein, a. said muddriven turbine means has a rotatable eccentric weight reciprocator meansconnected thereto for being reciprocated and vibrated thereby; and b.said percussion bit means is connected to said rotatable eccentricweight reciprocator for being reciprocated thereby.
 5. A drill stringhaving a plurality of drill pipes with drilling mud flowing downwardlyand internally thereof to the bottom comprising, a. a drill collarattached to the lower end of the lowest drill pipe for receiving adrilling mud therethrough from above, b. a drill bit mechanism mountedon a lower end of said drill collar for receiving said drilling mud, c.mud driven turbine means rotatably mounted in an upper portion of saiddrill collar for being rotated by said drilling mud as it passes down tosaid drilling mechanism, d. said mud driven turbine means is connectedto said drilling mechanism for operation thereof about the center lineof rotation of said mud turbine, e. said drill bit mechanism comprises arotary bit means and a percussion bit means, f. said rotary bit meanscomprises three spaced apart roller bits rotatably mounted to the lowerportion of said drill collar, g. said percussion bit means comprisesthree prongs extending laterally from the bottom of a vertical shaftextending downwardly from said mud driven turbine means, h. each of saidpercussion drill bit means three prongs is equally spaced between saidthree roller bits, and i. said percussion bit means is responsive tosaid mud driven turbine means for reciprocal movement between saidspaced apart roller bits for providing a very efficientpercussion-rotary drilling mechanism.
 6. A drill string as recited inclaim 5 wherein, a. said mud driven turbine means has a rotary camconnected thereto for being rotated therewith, and b. said percussionbit means has a cam follower moveably mounted on said rotary cam forgenerating reciprocal movement in said percussion bit means.
 7. A drillstring as recited in claim 5 wherein, a. said mud driven turbine meanshas a rotatable eccentric weight reciprocator means connected theretofor being reciprocated thereby, and b. said percussion bit means isconnected to said rotatable eccentric weight reciprocator for beingreciprocated thereby.
 8. A drill string as recited in claim 5 wherein,a. said elongated turbine wheel lower end has an arcuate cam fixedthereto for rotation therewith, and b. said drill bit mechanism has acam follower roller mounted on said arcuate cam for generatingreciprocal movement in said drill bit mechanism as said arcuate camrotates with said mud driven elongated turbine wheel.
 9. A drill stringhaving a plurality of drill pipes with drilling mud flowing downwardlyand internally thereof to the bottom comprising, a. a drill collarattached to the lower end of the lowest drill pipe for receiving adrilling mud therethrough from above, b. a drill bit mechanism mountedon a lower end of sai drill collar for receiving said drilling mud, c.mud driven turbine means rotatably mounted in an upper portion of saiddrill collar for being rotated by said drilling mud as it passes down tosaid drilling mechanism, d. said mud driven turbine means is connectedto said drilling mechanism for operation thereof about the center lineof rotation of said mud turbine, e. said mud driven turbine meanscomprises an elongated turbine rotor having upper and lower ends mountedaxially in said drill collar in bearings at each of said ends of saidelongated turbine wheel, f. said elongated turbine wheel lower end isconnected to said drill bit mechanism for operation thereof, g. saidelongated turbine wheel lower end has a rotary Eccentric weightreciprocating mechanism connected thereto comprising a worm drive inrotating contact with a worm gear fixed to an eccentric weight forgenerating reciprocal motion with rotation of said elongated turbinewheel lower end, and h. said drill bit mechanism has a percussion bitmeans fixed to said rotary eccentric weight reciprocating mechanism forbeing reciprocated thereby with rotation of said mud driven elongatedturbine wheel.
 10. A percussion-rotary drilling mechanism as recited inclaim 9 wherein said reciprocator means comprises, a. a cam plateconnected to the bottom of said mud driven turbine means to rotatetherewith, and b. cam rollers mounted on said percussion drilling meansand operable on said rotatable cam plate for generating reciprocalmovement in said percussion drilling means.
 11. A percussion-rotarydrilling mechanism having a plurality of drill pipes with drilling mudflowing downwardly and internally thereof to the bottom comprising, a. adrill collar attached to the lower end of the lowest drill pipe forreceiving a drilling mud therethrough from above, b. a drill bitmechanism mounted on a lower end of said drill collar for receiving saiddrilling mud, c. mud driven turbine means rotatably mounted in an upperportion of said drill collar for being rotated by said drilling mud asit passes down to said drilling mechanism, d. said mud driven turbinemeans is connected to said drilling mechanism for operation thereofabout the center line of rotation of said mud turbine, e. said muddriven turbine means comprises an elongated turbine rotor having upperand lower ends mounted axially in said drill collar in bearings at eachof said ends of said elongated turbine wheel, f. an eccentric weighthaving a worm gear fixed thereto and rotatably mounted on saidpercussion drilling means, g. a worm drive mounted on the bottom of saidmud driven turbine means to rotate therewith, and h. said rotatableeccentric weight worm gear being mounted in operable engagement withsaid rotating worm drive for generating reciprocal movement in saidpercussion drilling means.